106 H. A. Nicholson — On the Lake District. 



seen, dipping S.S.E. at 55^^, and shortly succeeded by a felspatliic 

 trap, the inclination of which could not be determined. Proceeding 

 westwards, no sections are obtainable till Mosedale Beck is reached 

 at a distance of about a mile and a half. Here the shaly, ujDper 

 beds of the Skiddaw Slates are seen just below the road from 

 Matterdale to Threlkeld, dipping N.N.E. at 55° ; and surmounted 

 by the massive trap which forms Wolf Crags. For a short distance 

 to the west of Mosedale Beck the Skiddaw Slates ai"e separated from 

 the lowest trap of the Green Slates by a boss of intrusive felstone 

 derived from the syenite of the vale of St. John. The two shortly 

 come together again, and are seen in a ravine in one of the eastern 

 sj)urs of Clough Head, where the dip of the Skiddaw Slates is from 

 45° to 60° to the S.S.E. All along the flanks of Clough Head the 

 upper beds of the Skiddaw Slates can be traced at a considerable 

 elevation, and overlaid by the felspathic trap before -mentioned. In 

 many places they are a good deal disturbed, and are often indurated 

 and penetrated by small veins of quartz, but the dip is mostly to 

 the S.S.E. at angles of from 30° to 50°. In the ravine which leads 

 from Threlkeld Common to Lowthwaite in the vale of St. John, the 

 Skiddaw Slates are seen near the top of the ascent, dipping S.S.E. 

 at 55°. They appear to be continued underneath Wanthwaite Crag, 

 nearly as far as Lowthwaite, the same felspathic trap appearing to 

 rest upon their upturned edges for the whole distance ; but this is 

 perhaps due to faulting, as the country is a good deal disturbed, and 

 there is no clear section. 



On the opposite side of the vale of St. John {i.e., the western 

 side), an intrusive syenite intervenes between the Skiddaw Slates 

 and Green Slates. There is still, however, evidence of a want of 

 conformity. Thus all along the flanks of Naddle Fell a succession 

 of bedded traps and greenstones, with intercalated thin bands of 

 ashes, is exceedingly well displayed, forming a series of oblique 

 terraces, which dip S.S.E. at about 30°. The angle of dip, there- 

 fore, of the lower part of the Green Slate Series is very markedly 

 lower than the dip of the Skiddaw Slates on the opposite side of the 

 valley, and indeed in almost all localities, since this is usually 

 between 45° and 65°. The same low inclination of the Green Slate 

 Series is equally well exhibited in the parallel valley of Naddle 

 Beck, in the northern end of Castlerigg Fell. Between the vale of 

 St. John, however, and the town of Keswick, the upward termina- 

 tion of the Skiddaw Slates is not seen, as the country is thickly 

 covered with drift. 



In the bed of the Greta, in Keswick, the Skiddaw Slates are seen 

 dipping southward at high angles, and succeeded to the south by 

 the greenstone of Castle Head, a little wooded hill close to the 

 town. On the western side of Derwentwater the junction between 

 the two formations can be traced about half a mile to the south 

 of Portingscale. Thus the wooded hill, called Fawe Park, is com- 

 posed of the upper beds of the Skiddaw Slates, dipping S.S.E. at 

 from 40° to 50°. These are succeeded at Eosetrees by a felspathic 

 trap, immediately succeeded to the south by the Skiddaw Slates 



